In a small bowl mix the harissa paste, honey and the juice from 1 lemon.
Rinse and pat dry the chicken. Place in a plastic bag and add the harissa honey mixture and seal. Refrigerate overnight. (See Note 1)
Start grill and heat to 350°F.
Grill for about 12 minutes on each side. Using tongs carefully lift the drumsticks off the grill to ensure that the skin is not sticking to the grill. (See Note 2)
In the last 3 minutes of grilling add the other three lemons cut in half to grill along with the tomatoes.
Remove from grill and allow to rest 5 minutes then brush with remaining tablespoon of honey.
Serve immediately with extra harissa paste on the side with chopped cilantro for garnish.
Notes
1. I marinate the chicken overnight for maximum flavor penetration, but feel free to coat and grill, basting with more if needed while grilling. The reason I marinate overnight is to keep the grill closed while the chicken is grilling. That keeps an even temperature. 2. I think cooking the drumsticks to the internal temperature of 180°F works well with the dark meat of the chicken where the required internal temperature is usually 165°F.